I have tried the advice to add the internal loop (127.0.0.1) to the network card on the Windows 2008 R2 DNS Server in IPv4. This is added under the actual DNS Server IP address.
It does not work.
If the workstation is rebooted still 5 of the 9 computers are not present in the network explorer.
If I stop Malwarebytes then click on network explorer all the workstations are seen.
We have Malwarebytes only on the machines that are active on the Internet and it is happening with every one.
Are there other suggestions?